Standard: BS 2693
Available sizes: 1/2 to 9/16 (7 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 8 | 0.8594 | 0.9827 | 0.9935 | 0.9835 | 0.9727 | 0.9316 | 0.9262 | 0.9935 | 0.9827 |
| 1/4 | 18 | 0.2508 | 0.303 | 0.309 | 0.308 | 0.302 | 0.2829 | 0.2799 | 0.309 | 0.303 |
| 3/8 | 12 |
Standard corrosion protection for indoor and mild outdoor environments.
Salt spray: 96–200 hours | RoHS compliant (trivalent chromium)
High-performance coating for automotive, marine, and harsh environments.
Salt spray: 720–1500 hours | Recommended for grade 8.8+
Heavy-duty protection for structural and outdoor applications.
Salt spray: 500–1000 hours | Thread tolerance adjustment required
Note for high-strength fasteners (Grade 10.9, 12.9): Electroplating processes require hydrogen embrittlement relief baking (minimum 4 hours at 200°C within 4 hours of plating). Contact our engineering team for grade-specific plating recommendations.
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
| 0.4695 |
| 0.5495 |
| 0.558 |
| 0.554 |
| 0.546 |
| 0.5176 |
| 0.5136 |
| 0.558 |
| 0.5495 |
| 5/16 | 14 | 0.3579 | 0.4258 | 0.433 | 0.4305 | 0.4233 | 0.3991 | 0.3955 | 0.433 | 0.4258 |
| 5/8 | 6 | 1.3127 | 1.4788 | 1.493 | 1.481 | 1.467 | 1.4089 | 1.4018 | 1.493 | 1.4788 |
| 7/16 | 10 | 0.6378 | 0.735 | 0.744 | 0.736 | 0.727 | 0.6955 | 0.6910 | 0.744 | 0.735 |
| 9/16 | 7 | 1.0890 | 1.2312 | 1.243 | 1.232 | 1.22 | 1.1715 | 1.1656 | 1.243 | 1.2312 |
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